import 'dart:convert';
import 'dart:math';

import 'package:flutter/material.dart';
import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
import 'preview_tile.dart';

import 'api/api.dart';
import 'platform.dart';

class ShuffleScreen extends StatefulWidget {
  const ShuffleScreen({Key? key}) : super(key: key);

  @override
  State<ShuffleScreen> createState() => _ShuffleScreenState();
}

class _ShuffleScreenState extends State<ShuffleScreen> {
  late Future<List<VideoT>> _data;

  Future<List<VideoT>> loadData(int nr) async {
    final data = await API.query("video", "getRandomMovies", {'Number': nr, 'Seed': Random().nextInt(0x7fffffff)});

    final d = jsonDecode(data);

    List<VideoT> dta = (d['Videos'] as List).map((e) => VideoT.fromJson(e)).toList();

    return dta;
  }

  @override
  void initState() {
    super.initState();

    _data = Future.delayed(Duration.zero).then((_) {
      double width = MediaQuery.of(context).size.width;
      return loadData((isTV() ? width ~/ 200 : width ~/ 330) * 2);
    });

  }

  @override
  Widget build(BuildContext context) {
    double width = MediaQuery.of(context).size.width;
    return FutureBuilder<List<VideoT>>(
      future: _data, // a previously-obtained Future<String> or null
      builder: (BuildContext context, AsyncSnapshot<List<VideoT>> snapshot) {
        if (snapshot.hasError) {
          return Text("Error");
        } else if (snapshot.hasData) {
          return Column(children: [
            MasonryGridView.count(
              shrinkWrap: true,
              // every tile should be at max 330 pixels long...
              crossAxisCount: isTV() ? width ~/ 200 : width ~/ 330,
              mainAxisSpacing: 4,
              crossAxisSpacing: 4,
              padding: EdgeInsets.all(5),
              itemCount: snapshot.data!.length,
              itemBuilder: (context, index) {
                return PreviewTile(dta: snapshot.data![index]);
              },
            ),
            const SizedBox(
              height: 25,
            ),
            TextButton.icon(
                onPressed: () {
                  setState(() {
                    _data = loadData((isTV() ? width ~/ 200 : width ~/ 330) * 2);
                  });
                },
                icon: const Icon(Icons.update),
                label: const Text("Shuffle"))
          ]);
        } else {
          return Column(children: const <Widget>[
            SizedBox(
              width: 60,
              height: 60,
              child: CircularProgressIndicator(),
            ),
            Padding(
              padding: EdgeInsets.only(top: 16),
              child: Text('Awaiting result...'),
            )
          ]);
        }
      },
    );
  }
}